Switched reluctance motor attracts great attention owing to its simple and firm structure, low manufacturing cost and good speed control performance. However, its special double salient structure and switch-type exciting mode make the electromagnetic torque it outputs have large ripple, seriously affecting its application fields. For this, the researchers provides various methods to eliminate torque ripple and meanwhile realize minimum copper loss. These methods obtain a good effect within certain speed range. Nevertheless, when the rotational speed is high, due to limited DC supply voltage, the ability of the system to control and track desired current, desired flux linkage and desired torque is weakened and it is difficult to effectively eliminate torque ripple. Furthermore, due to the limitation of maximum endurable current of winding and the volt-ampere capacity of semiconductor devices, switched reluctance motor system has an upper limit of current and the limitation of current makes switched reluctance motor only is able to output smooth torque within a limited range. Therefore, all the controls over output of smooth torques have a specific operable range.